Mitchell and I installed the TMDs on the HAM ISI Blade Springs similar to as Hugo and I did on WHAM3.  Mitchell has the serial numbers.  There were also a couple feedthrus that needed to have the in-vac cable attachment screws secured.  Mitchell did this.

WP4464. Brian, Fabrice and Dave.

Following the restarts of all the recompiled front ends yesterday Fabrice noticed that the BSC ISI watchdogs were being reset a few seconds after tripping.

We tracked the problem down to a modified common C-code file which was installed on the HAM ISI systems but not on the BSC ISI.

The C-code is isi/common/src/ISIWD_GPS.c. Its number of inputs was increased to accomodate the hardware watchdog system. The HAM ISI common model (isihammaster.mdl) was updated to the new code but the BSC common model (isi2stagemaster.mdl) was not.

The solution to get the BSC ISI systems operational today is to make a copy of the older version of ISIWD_GPS.c called ISIWD_GPS_OLD.c and change the isi2stagemaster.mdl to use this file (with the smaller number of inputs) in both stages. Brian and Fabrice will now work on isi2stagemaster to use the new code. For now LHO's isi2stagemaster.mdl will remain a locally modified not submitted to SVN, and the ISIWD_GPS_OLD.c will remain a local file not added to the repository.

We built,installed and restarted h1isibs and Fabrice tested the watchdog, it is functioning correctly. We will restart the rest of the BSC ISI this afternoon when the opportunity arises.

As mentioned previously, we have been testing the new ISI_HAMX guardian infrastructure on HAM4, in preparation for deployment on HAMs 2 and 3.

At this point things are looking good to go.  We've interated with the Stanford SEI team to iron out all the configuration and behavioral issues.  We made one last change to the DEISOLATION state to smooth out the isolation gain ramp down (userapps svn r7300), and it seems to be working fine.  We've now gone through many cycles of changing to all the full isolation levels, and everything looks good.  Therefore I think we're ready to move on to HAM2 and HAM3:

Deployment of HAM2 and HAM3 ISI Guardians will commence at 07:00 PST, February 27, 2014.

We will seize this target of opportunity tomorrow morning while the SUS and ISC teams are running suspension actuator diagnolization measurements on ITMX.  They have confirmed that theeir measurements will likely run through the early afternoon, so we will start early to make sure we have plenty of time to test the code.  The basic testing procedure will be:

1. note/store all current target offset values
2. reset the CPS target offsets
3. store the newly reset target offsets
4. run through all states
5. set targets to large offsets (150 um/urad)
6. run through all states

If the behavior looks good, we will leave the ISI_HAM2 and ISI_HAM3 guardians running.

Yuta, Kiwamu,

We continued working on the alignment automation this morning. Today's emphasis was on the dither alignment of PRY. It is now successfully coded in the LSC guardian.

The next step is to make the PRX and PRY dithering systems sequential so that we can run them by pressing only a single button.

Dither alignment:

Currently we use Stefan's IAL to dither ITMY. The POP18 signal is temporarily routed to the ADC and demodulated in IAL. Since the middle masses didn't give us a big excitation in the angle, we decided to use the top mass to excite the angular motion at around 2 Hz for pitch and yaw. The demodulated signal is also fed back to the top mass. This worked pretty well.

The guardian was modified to include the dither alignment. We checked the functionality a couple of times by going through the initial state to the dither state. It is functional although we are not 100% confident with our guardian code.

I zero-ed out the optical levers today, HAM3 looked especially bad but this was because the QPD cable was unplugged from the whitening chassis.  Please don't do this.

Daniel, Keita, Stefan

For yesterday's IMC mystery we wanted to go back and look at the HAM2 optical lever to assess HAM2 rotation. Turns out it didn't move, but HAM2 is doing something funny over a 2day or so period.

Kiwamu and Dave.

Kiwamu made two restart of the h1suspr2 model, both required DAQ restarts to ingest the new INI files. The times of the DAQ restarts are

10:14 and 10:30 PST

[Ed, Evan]

We are preparing to make a measurement of the length of the PRC using the phase-locked auxiliary laser technique described by Chris Mueller (T1400047). Previously, this has been used to measure the Livingston IMC length (LLO alog 9599).

We set down a 520 mW Lightwave NPRO on the IOT2R table, along with a Faraday isolator and steering mirrors. We will inject this beam into the PRM_refl side of the IOT2R periscope. The beam will hit the back of IM4, and a small fraction (2400 ppm) will be transmitted toward the PRM. This gives 1.2 mW of auxiliary power on the PRM, compared to 9 mW of 45MHz PSL single-sideband power on the PRM.

Most of the auxiliary power should reflect from the back of IM4 and return to the IOT2R table via the IO_forward side of the periscope. For mode-matching, we hope that we can simply send part of the IO_forward beam onto a New Focus 1611 and maximize the observed beat. Currently, there is 3 mW of power in the IO_forward beam.

Using this beat, or otherwise, we will phase-lock the auxiliary laser to the PSL carrier beam. Then with PRMI locked on the PSL sideband, we will sweep the offset to the auxiliary PLL and monitor the RF coming out of POPAIR_B. We should see the strength of the RF reach a maximum whenever the auxiliary beam is coresonant with the the PSL sideband. By tracing out the Lorentzian profile of the RF amplitude across successive resonances of the PRC, we can extract the FSR of the PRC. Given a design length of 57.6557 m, we expect an FSR of 2 599 850 Hz. If we can measure the FSR to within 100 Hz, we can get the PRC length to within 2 mm.

While pulling Dial Indicators at BSC9 yesterday I eyeballed the fluid catches and found the horizontal full and starting to drip.  I cleaned up the catch and reinstalled.  This hasn't been leaking as badly as the BS V2 had been but only no drips is tolerable.  Changing this out will take HEPI down for a few hours--look for that next Tuesday.

HugoP reported on 12 Feb that we had an issue with the EndX HEPI being unable to tilt completely.  We were requesting 390000nrads but only getting 350000.  Hugo pushed it more and it went more but it would never go to the fuly requested value.  Hint, hint--like there was an offset in the path...hummmm

I can't find an entry in the alog around Jan21, when this offset in the position request showed up (see Hugo's first link.)  However, when I look a little deeper I find the offset was increase to 39000 on Friday Jan 17 by me to run the RY Tilt manually (I guess it shoould have been 390000.)  It looks to me that on Monday the 21st, myself or Sebatian turned the HEPI position loops on but failed to turn off the offsets giving the offset observed since then.  Obviously our 'greening' of the system must be more robust.

I found this yesterday after the RCG upgrade reboot attempting to get the system back on.  The safe.snap was problematic so Dave reloaded form the 9am burt.

So by removing these offsets, the HEPI will now tilt that much more.  If the alignment is intolerable, change the target/current setpoint on the DC BIAS medm from -389800 to -350000.

Pretty much as Fabrice directed and Shiela & Kiwamu report .  One notable: The ITMX HEPI is off, not tripped.  I think the safe.snap/burt restore process/setup for the SEI is troubled and needs attention.  I guess that mainly means my job.

Unless someone tried to get the ITMX HEPI on and then left it in an unusual state, it came up screwy: Specifically--the Master switch is closed and the ISO gain is 1.0 but the Position Bias Screen is all zero.  All the switches and filters are off on the IPSINF screen but the Switches are on and the filters are off on the L4CINF page.  Etc etc... 

This morning, Yuta complained that the alignment of PRY changed a lot and therefore he had to tweak either BS or ITMY by 60 urad or so --- of course, HEPIs and ISIs were tripped on ITMY and BS (see alog 10333).

After untripping them, we comfirmed that the alignment came back to where it should be without touching the suspension biases. The ISIs are currently in the damping mode.

They are now:

• BS
  • HEPI
    • Level 2
  • ISI (see Fabrice's alog also )
    • stage 1 damped
    • stage 2 damped
    • no isolation engaged
• ITMY
  • HEPI
    • Level 1
  • ISI
    • stage 1 Level 3 isolation damped
    • stage 2 Level 3 isolation damped

I found that ITMY had been tripped at the L1, L2 and L3 watchdogs. I untripped them. It is now in "aligned" state.

Arnaud, Sheila

We want to try the ETM drive diaonalization.  One reason is that we can see that our longitudnal feedback to the top mass is causing pitch motion of the optic, and we will need the full drive diagonalization when we get the Y arm anyway, so we might as well do it now.  

We had some disscussion about how to balance the coils when there are only 3 osems, in the end we decided to just do length 2 yaw, and then move on to measureing transfer functions.  Tonight Arnaud and I had a first attempt at doing the length 2 yaw measurement, we just applied DC length offsets and used the OpLevs.  This may need to be corrected if the OpLev calibration is revisited tomorow....

When we started there was a -0.004 in the length 2 yaw drivealign matrix, we could not tell from a search through the alog and talking to various people in the control room where this number came from, possibly it was copied over from ETMY.  We have now replaced this with -0.0024.  

Attached is a plot of our measurements and the script we used. 

Daniel, Ed, Yuta, Stefan, 

After this morning's boot fest we noticed that the IMC reflected beam was completely misaligned, missing camera and WFS, and barley hitting the LSC diode. Interestingly, the IMC still locked with good build-up. We checked HPI, ISI and all involved SUSs for any drift. None showed any. Also, the PRX cavity still nicely locked. So we concluded that some mirror on IOT2L must have moved, and realigned that whole beam path. Everything worked fine again afterwards.

In the process we also had accidentally moved an ASC POP picomoter (#6) horizontally (yaw). We were able go find the beam again, but once again confirmed that these picomotors are hugely asymmetric, i.e. the counters are only useful for suggesting an axis and direction.

Written by Yuta

This morning, I could dither PR2 and PRM from ASC-ADS, but I can't now.
For example, even if I put on H1:ASC-ADS_PRM_PIT_OSC, the signal doesn't show up at H1:SUS-PRM_M3_ISCINF_P_IN1.
Since it did this morning(6AMish~10AMish), I suspect this is related to the boot festival today.

If I lookup the simulink diagram, h1asc.mdl has H1:ASC_SUS_PRM_PIT_DITHER, but h1prm doesn't.

[PRMI dither alignent work this morning]
We want the alignment automation to speed up the PRMI commissioning.

I checked the guardian script for PRX dither alignment Evan and I made yesterday. It now works for PR2 dither alignment. PRX_ALIGN state closes PR2 (and PRM) dither alignment loop, wait for a while, and offloads the feedback offset (e.g. H1:SUS-PR2_M1_LOCK_P_OUT) to the alignment slider values (e.g. H1:SUS-PR2_M1_OPTICALIGN_P_OFFSET).
For PRM, I had to lower the excitation frequency for pitch/yaw from 14/11.5 Hz to 5.4/7.2 Hz, and excite not only M3 but also M2 to get the error signal. I haven't checked fully yet, but the guardian script should also work for PRM dither alignment.

Next work is to do BS(or ITMY) alignment using PRY.

We have been experiencing issues with the BSC-ISI watchdogs since the models have been re-compiled this morning. They are not operating as they should. It may or may not be related to the rcg code update (it could also be due to some piece of SEI code that should not have been updated from the svn, for example). We have not found any obvious cause of the problem yet. The BSC-ISI units are currently working fine and safely in damping mode. As a measure of precaution, the master switches will be turned off at the end of the day.

This is from last week.

We briefly measured the distance between optics and such, and used nanoscan to measure beam width/profile at various places though they were very very ugly.

See attached scribbling for layout (all dimensions in inches). Mirror names are arbitrary.

Measurement points are indicated by alphabet from A to I. Measurement points with prime (G'-I') means that the first lens in WFSB path (LWFSB1) was removed during the measurement.

The rest of the attachements are the nanoscan result. WFSB1.jpg-WFSB4.jpg=measurement point A-D. WFSA1.jpg and WFSA2.jpg=measurement point E and F. WFSC1.jpg-WFSC3.jpg=measurement point G', H' and I'.